Apparatus for printing motion-picture films



H. R. EVANS. DECD.

A. K. EVANS. EXECUTRIX,

APPARATUS FOR PRINTING MOTION PICTURE FILMS. APPLICATION FILED JUNE 1.1915. RENEWED JAN. 7.1922.

1 ,425,46 1 Patented Aug. 8, 1922,

HEET 1.

3 SHEETSS hveJufar Mk'Zneslses.

H. R. EVANS, DECD. A. K.IEVANS, EXECUTRIX. APPARATUS FOR PRINTING MOTIONPICTURE FILMS- APPLICATION FILED JUNE l, 1915. RENEWED JAN. 1,1922.

1 ,425946 1 Patented Aug. 8, 1922.

3 SHEETS-SHEE 2.

y INVENTOR ATTORNEY H. R. EVANS, DECD.

A K. EVANS, EXECUTRIX, APPARATUS FOR PRINTING MOTION PICTURE FILMS.

APPLICATION FILED JUNE I, I915. RENEWED JAN. 7. I922.

PatentedA ug- 8, 1922. s SHEETS-SHEET 3.

' apparatus for preparing the films for the v UNITED STATES PATENTOFFICE.

HEN'RY RIEGEL EVANS, OF LONDON, ENGLAND; ADELE KEAN EVANS EXECUTRIX OFSAID HENRY RIEGEL EVANS, DECEASED.

APPARATUS FOR PRINTING MOTION-PICTURE FILMS.

Specification of Letters Patent.

Patented Aug. 8, 1922.

Application filed June 1, 1915, Serial No. 31,331. Renewed January 7,1922. Serial No. 527,800.

To all whom it may concern Be it known that I, HENRY RIEGEL EVANS, acitizen of the United, States of America, residin at London, England,formerly of New ork, United States of (America, have invented certainnew and useful Improvements in Apparatus for Printing Motion- PictureFilms, of which the following is a specification.

This invention relates to the formation of pictures upon amotion-picture film or the like of the kind intended to give a colouredeffect by employing light of one colour with one picture and light ofanother colour with another picture, and blending the results soobtained to give the desired effect. Films of this kind are sometimesprepared for use with two colours only, in which the pictures areilluminated alternately with red and green lights, and thetwo colouredeffects blended on the screen or in the eye of the observer. More thantwo colours may,

however, be employed if desired and are then employed in arecurringcycle of changes.

- An object of this invention is to provide proJection of colouredmotion-pictures to obtain a colour effect better than, or differentfrom, that which would have been obtained had the films'been prepared inthe usual manner.

According to the present invention there is provided apparatus for thepreparation of pictures of the kind described, by the use of which thedensity-relation between pictures to be used in co-operation with oneanother but for different colours, is made to be different from thedensity-relation that would have been obtained in theordinary way fromor in the corresponding primary photographs. The obiect of making thisdiiferent is to make the relative proportions of the colours seen in theultimate result different from what they would otherwise be i. e.different from the density-relation which would ensue if the presentinvention did not intervene to bring about an intentional modificationof the ratio. It may be desirech'for example, to accentuate one colourmore than was the case with the original object represented, or it maybe desired to correct a want of sensitivity in the photo aphic film tothat particular colour, in which case the density of the positivepictures for this colour will be made less in relation to the otherpictures than it otherwise would have been.

According to the present preferred form of apparatus embodying myinvention, pictures to be used for one colour are photoprinted with abeam of light the printing effect of which is different from thatemployed for those to be used for another colour, the two effects havinga chosen ratio; the pictures for the different colours are for somemethods of exhibition arranged on different films but this process isapplicable as hereinafter described whether the pictures are so arrangedor whether those for different colours are upon the same film.

-Apparatus arranged to vary the printing effect of the light preferablydoes so auto mat1cally in a recurring cycle and may further be arrangedor constructed so as automatically to change the relation between thedifferent printing effect employed.

By way of illustration a construction of apparatus for two-colour workis hereinafter described with reference to the accompanying drawings inwhich Figure 1 is perspective view showing the arrangement of light andobturator disc for printing; 1

Figure 2 is a side elevation, partly in section and with certain partsbroken away, showing the film-feeding mechanism;

Figure 3 is an elevation of a modified obturator disk Figure 4 is aplan, partlyin section, of the.

apparatus of Figure 3; and

Figure 5 is an explanatory diagram. The apparatus shown in Figure 1includes a source of light A, a window B through which the light from Apasses to printing apparatus of a well-known kind for printingkinematograph films, and an obturator disc C interposed between thesource of light A and the window B. The apparatus illustrated isarranged for printing a film for two-colour work.

The obturator disc is so geared to the printing apparatus as shown inFigure 2 that it makes one com lete revolution for every two pictures ont e film moved past the window. The printing apparatus is construeted inthe well-known manm: o allow each picture to be stationary 01m- ;e thewindow at the time when an O 'FJ1.l!1g in the obturator disc allowslight to reach the window B, and consists ofthe well knownintermittently-operated feed sprocket 2 engaging the film 1 to move itstep by step past the window, the sprocket 2 being mounted on a shaft 3with a star or Geneva wheel 4 operated by the pin 5 carried in disk 6which in turn is mounted on shaft 7 the star wheel pin and diskconstituting the well known (ireneva movement. The shaft 7 is in turndriven by vertical shaft 8 through bevel pinions at the rear of disk 6(not shown), and shaft 8 in turn is driven through bevel pinions 9 and10 supported by bracket 11 and having a 2:1 ratio, so that shaft 8 willbe driven twice as fast as shaft 12 to insure the movement of twopictures past the window for each revolution of the obturator disk C asmentioned, and as is well understood in the art. Shaft 12 carries at itsfront end (Fig. 1) the sprocket 13 which is geared as shown to sprocket14 on the shaft of the obturator disk, so that the obturator diskandxthe film-moving mechanism are geared together to operate in themanner described. Shaft 12 may be driven in any suitable manner such forexample as by a bevel gear (not shown) meshing with gear 10, as is wellunderstoodin the art.. If desired, a suitable loopforming sprocket 15may also be provided, as is customary, above the gate as shown, and thisin turn may be driven from the same source of power that drivesthe shaft1 as is well understood in the art. 16 shows diagrammatically the usualfilm clamp at the gate, which may be operated in any well known manner,from the same source of power that drives shaft 12 and "sprocket 15, asis well understood in the art.

The above described film-feeding mechanism of F 2 is one \of the wellknown standard types of feed, and I make no claim to the same. (rated inthese figures is arranged for twocolour work and the disc C has twoopen- 45 ings in it-C .andC one of which, C has a larger effective areathan the other. In consequence of the difference of effective areas in Cand C the pictures for one colour, namely, those printed by the lightadmitted by the aperture C receive light of less duration and are lessdensely printed than those for the other colour for wh ch light istransmitted for a period of longer duration through the apertureC? Iffor example it is desired 51o somewhat aoeentw ate the .roportion of redin the final result .obtain when the pictures are projected, thepositive pictures to be projected through .a red colour filter may beexposed through th aperture C so that being less dense than thoseexposed through C they will allow more light to pass than those will.

. Preferably one of the apertures, for example the aperture C in theobtflrator disc,

\ 65 i6 adjustable. One construction to provide The apparatus illusforthis is that shown in Figure 1 where an adjustable leaf D is movableabout the axis of rotation of the disc to close the aperture C to anydesired amount; the leaf D is secured inthe adjusted position by amilled nut E on a screwed pin engagin with .a slot D in the leaf.

Vhere it is desired to produce a radual change in the relative strengthsof t I e component colours, a portion of the obturator may beconstructed as shown in Figures 3 and 4. In this construction leaf D isautomatically shifted every revolution by means of a star wheel F whosefingers strike a in K as the disc rotates. The star wheel is mounted onthe end of a worm G gearing with a worm wheel G and this again ismounted on a worm H 'earin with a worm wheel H on the spindle of t 1eworm wheel H is secured a pinion H engaging with a toothed segment rackJ secured to the leaf D.

The pin K is preferably displaceably mounted and for this purpose may besupported in the manner illustrated, that is by being mounted upon asleeve K By this means the change in effective value of the aperture Cmay be made to commence or stop at any desired moment without stop pingthe rotation of the obturator merely by the operation of sliding the pininto and out of the position in which it engages with the star wheel.

In order to provide for reverse movement of.the leaf D a second pin K ispreferably provided on the sleeve KR. A gap is left between the pins Kand K sufficiently wide to clear the star wheel F so that when thesleeve K is in the midway position the wheel F is not operated.

In order to provide for quick setting by hand of the leaf D the pinion His slid-ably mounted upon its spindle and can be dis- .laced axially bypulling the knob H.

hen thus axially displaced the pinion no lon er engages with the rack Jand the leaf D may then be readily set by hand.

The source of light A is preferably slidably adjustable towards and awayfrom the window B in a well-known manner to give 5 the desired printingstrength.

Figure 5 serves to illustrate diagrammatically the result obtained bythe aid of this invention. In this diagram L indicates a strip ofkinematograp'h film with ict-ures 12o taken alternately through red andgreen screens, the pictures being denoted in the diagram by the areasmarked 1' and 9 respectively. For the purpose of this exemplificationthese pictures 1', g constitute what are herein referred to as the primphotographs. The relative densities of ese two sets of pictures areindicated by the shading as being substantially e ual. At L is indicateda strip of film prlnted from the strip L in which the areas 1' and 9correspond with those at 1' and g respectively, but by reason of theprocess employed the densityrelation between T and g is diiferentfromthat bet-ween r and g. I

lit is to be understood that the apparatus hereinbetore described indetail is given by way of example and that this invention is not limitedin-its scope to such details. It will also be understood that theexpression primary photographs hereinhe'l'ore employed must beinterpreted as including the images which would have been developed uponthe negative had they all been treated alike and not subjected to theprocess which is the object of the present invention.

Moreover the apparatus may obviously be modified without the exercise ofinventive skill so as to be suitable for three-colour work or for morethan three-colour work.

it will be obvious to those skilled in the art, after understanding myinvention, that various changes in and modifications of the apparatusherein shown and described may be made without departing from the spiritand scope of the invention, and l aim in the appended claims to coverall such changes and modifications as are within the spirit and scope ofthe invention.

lin view of the various embodiments that my invention may take, it donot wish to be understood as limiting myself to the particular methodand apparatus shown, nor otherwise than as indicated in the appendedclaims.

What I claim as m invention and desir to secure by Letters atent is 1.in printing apparatus for motion pictures, the combination of anexposure window, means for moving past said window a film havingdifferent sets of pictures thereon to be reproduced in colors, a sourceof light the rays from which are directed upon said window, and meansfor so varying the printing efiect of the light falling upon said windowthat it passes through a periodically recurring cycle of changes whichsynchronize with the changes of'thepictures of the different setsappearing at the window.

2. lln printing apparatus for motion pictures, the combination of anexposure'window, means for moving past the window a film havingdili'erent sets of pictures thereon to be reproduced in colors, a sourceof light the rays from which are directed upon said window, a device forreducing the printing effect of the light falling upon said film,

and means for moving said device into the light beam being directedthrough said window in a periodically recurring cycle of changes whichsynchronize with the changes of the pictures of the different setsappearing at the window.

3. In printing apparatus for motion pictures, the combination of anexposure window, means for moving past the window a film havingdifferent sets of pictures thereon to be reproduced in colors, a sourceof light the rays from which are directed upon said window, a device forvarying the printing effect of the light falling upon said film, meansfor moving said device into the light beam being directed through saidwindow in a periodically recurring cycle of changes which synchronizewith the changes of the pictures of the different. sets appearing at thewindow, and means co-operating with said light-varying means forautomatically varying the eifect of said light-varying device upon thefilm as the printing operation proceeds.

a. In printing apparatus for motion pictures, the combination of anexposure window past which a film having different sets of picturesthereon to be reproduced in col- 01's is moved step by step, a sourceoflight the rays of which are directed upon said window, a shutterhaving a plurality or openings therein, means for rotating the shutterso that a certain one of said openings appears in register with thewindow synrhronously with the pictures of one of said sets while anothershutter opening appears synchronously with the pictures of another set.one of said openings being of greater light-transmitting capacity thanthe other and having means for varying its lightgraansmitting capacity,for the purpose speci- 5. in printing apparatus for motion pictures. thecombination of means for feeding a sensitized film and a filmhaving aseries of pictures thereon past a printing light, a shutter interposedbetween the source of light and the films, said shutter having aplurality or openings for exposing the films to the printing lightthrough said openings sequentially, one of said openings being largerthan the other, and means for rotating said shutter.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

HENRY RIEGEL EVANS.

Witnesses:

HAROLD H. Simmons, RoNAnn S. Donrnmonn.

